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Andre

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I made a lathe before, it worked great but needs a new spindle and it had lots of problems. So I thought I'd start a new one.
This one will be made of all scraps, I'm using what I have. I know it will be very small and not very strong since the X and Z slides will be made from .092" aluminum plate.
If this is successful, I will make a larger one from .25" steel plate. This one is only a prototype.

Here is all the scraps cut out to make the X and Z movements.

Milling the 45* angles with a 90* (metric) countersink. (on a thought, do metric countersinks have metric shanks?)

Andre

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Drilled holes for the female sides. They got spaced odd and look a little weird so next time I do a row of holes I will keep that mistake in mind. The head banging part is I had to do the other to match!

Edgefound with the tip of the center drill, put the piece up to the flat of one of the flutes and lightly tighten the vise. Then turn the center drill to the left (opposite of cutting direction) and it will move the part in the vise putting it on edge. Then move over half the diameter.

Drilling clearance holes for the now obsolete .110-50 screws. Luckily there were two taps in the jar of these screws, the thread size doesn't even come up on google.

Thank you! One side of the female slide will be fixed and the other side will have holes offset 20 thousandths towards the outside, so when I assemble it I can adjust one side of the female dovetail by tightening the .110-50 pitch screws on the loose side, clamping the male dovetail. Is that clear as mud? lol

If that was not clear, one side will be fixed and one will be oversized, but stay loose so I can adjust the tension on the male side.

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Ah, that makes sense, my ancient lathe is some what similar although it uses a captive screw to push the adjustable half into the dovetail. The bolts on the top are then tightened down to hold it in place. Might be an easier method of fine adjustment than holding them with your hand or a c clamp while you tighten the top bolts?

A

Andre

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Ah, that makes sense, my ancient lathe is some what similar although it uses a captive screw to push the adjustable half into the dovetail. The bolts on the top are then tightened down to hold it in place. Might be an easier method of fine adjustment than holding them with your hand or a c clamp while you tighten the top bolts?

I don't think it will be a big problem, the way I will make it is not the best (gib will be tilted into the male dovetail until it's nearly worn out), so I'll think about it. Thank you for the suggestion though! The way yours works is the same as a TAIG lathe, if I'm correct.

Today's update,

Drilled, tapped, and assembled one male dovetail to the bottom plate. This time I got the spacing right! Too bad nobody will see this row of screws as they will be on the bottom...

I put these screws in the spindle of my mill and used a lathe toolbit to flatten the domed screws. Since the screw slot is now thinner than it was before it stripped out a little, so I will replace the damaged ones when the slide is together.

And filed down the screws flush to the top.

Even though this stuff is small, it takes a long time to do, especially the hand work. I guess this is why we are hobby machinists.

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Nice work! I will be following you. Not that I will be building a lathe anytime soon, but this is still interesting to me. (way more interesting than what is on TV) Also I follow these be cause I almost always learn some new tricks, or something. thanks for thinking of the rest of the forum as you are doing this build. Mark

A

Andre

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Nice work! I will be following you. Not that I will be building a lathe anytime soon, but this is still interesting to me. (way more interesting than what is on TV) Also I follow these be cause I almost always learn some new tricks, or something. thanks for thinking of the rest of the forum as you are doing this build. Mark

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I like the dovetail made with no dovetail cutter. Very cool. How will you advance/retract it? (I assume this is the cross slide or compound) - where will the screw go? I have been tossing around ideas for a milling attachment, about the same size as what you've got there, and in my mind's eye, my milling attachment dovetail is thicker that yours to make room for a threaded half and an unthreaded half. Hard to explain, but you if you've ever used a taper lock bushing you probably can get the idea. The stationary (bottom) piece could have a half-moon channel milled down the center, with the channel stopping just short of the ends. A threaded rod would be cut to exact length and laid inside, so that 50% is below the surface and 50% is above. Then the mobile (top) piece would have a half-moon milled into it as well, but of smaller size (minor dia. of the threaded rod), and it would be threaded. I would probably accomplish this by drilling a long hole and tapping it, then filet the metal along the length of the hole. I think this would lend to a more robust cross-slide, as the threads would be engaged along the entire length of the cross-slide instead of just 5-10 threads engaged inside a puny brass nut, as it is in my lathe from the factory. Or i might be wrong; that design might just be asking for trouble, as the cavity collects shavings and they have nowhere to go but jam up the works. Only one way to find out...

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I like the dovetail made with no dovetail cutter. Very cool. How will you advance/retract it? (I assume this is the cross slide or compound) - where will the screw go? I have been tossing around ideas for a milling attachment, about the same size as what you've got there, and in my mind's eye, my milling attachment dovetail is thicker that yours to make room for a threaded half and an unthreaded half. Hard to explain, but you if you've ever used a taper lock bushing you probably can get the idea. The stationary (bottom) piece could have a half-moon channel milled down the center, with the channel stopping just short of the ends. A threaded rod would be cut to exact length and laid inside, so that 50% is below the surface and 50% is above. Then the mobile (top) piece would have a half-moon milled into it as well, but of smaller size (minor dia. of the threaded rod), and it would be threaded. I would probably accomplish this by drilling a long hole and tapping it, then filet the metal along the length of the hole. I think this would lend to a more robust cross-slide, as the threads would be engaged along the entire length of the cross-slide instead of just 5-10 threads engaged inside a puny brass nut, as it is in my lathe from the factory. Or i might be wrong; that design might just be asking for trouble, as the cavity collects shavings and they have nowhere to go but jam up the works. Only one way to find out...

Andre

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I like the dovetail made with no dovetail cutter. Very cool. How will you advance/retract it? (I assume this is the cross slide or compound) - where will the screw go? I have been tossing around ideas for a milling attachment, about the same size as what you've got there, and in my mind's eye, my milling attachment dovetail is thicker that yours to make room for a threaded half and an unthreaded half. Hard to explain, but you if you've ever used a taper lock bushing you probably can get the idea. The stationary (bottom) piece could have a half-moon channel milled down the center, with the channel stopping just short of the ends. A threaded rod would be cut to exact length and laid inside, so that 50% is below the surface and 50% is above. Then the mobile (top) piece would have a half-moon milled into it as well, but of smaller size (minor dia. of the threaded rod), and it would be threaded. I would probably accomplish this by drilling a long hole and tapping it, then filet the metal along the length of the hole. I think this would lend to a more robust cross-slide, as the threads would be engaged along the entire length of the cross-slide instead of just 5-10 threads engaged inside a puny brass nut, as it is in my lathe from the factory. Or i might be wrong; that design might just be asking for trouble, as the cavity collects shavings and they have nowhere to go but jam up the works. Only one way to find out...

Good question, I will have a little block screwed down to the underside of the male dovetail that will act as a nut, and make a bracket on the female that reaches down and holds the screw. Hopefully that makes sense. You'll see it later, good luck on the project! Keep in mind though if you use plates to make a segmented dovetail, if your machine is off any when machining your going to have to take that out during hand fitting. Not a big deal, but just make sure you have the time to do so, and if you don't I suggest using a dovetail cutter. They can be made with a radial arm saw and old lathe headstock, like I have done here: https://www.youtube.com/watch?v=mEeALuKCSfI

**********************UPDATE**************************

I've been doing a lot of work on the project yesterday and today, but just too lazy to post an update.

I will take a break on the cross slide, because when you see angles aluminum plates and small brass screws in your sleep somethings wrong! LOL

Before I left for Ohio, I PAD (Pencil Aided Design, thanks to DonB for the name) sketched a draft for the headstock and round bed.

Now to start work on the headstock,

Center and drilled for the spindle. I'm drilling a hair larger than the spindle, yet smaller than the OD of the copper bearings. So when I bore for the bearings they will press into a shoulder. I also drilled it in between, so I would have an oil reservoir covering the spindle, so it can slowly drip out through the bearings lubricating them.

Boring for the bearings using my homemade boring head (I finished it, yet need to update the thread). Kinda looks like a UFO.

Here you can see the bearings installed. They will be adjusted by a setscrew in the bottom. You can see how the oil will pool in the headstock (between the bearings), flooding the spindle. Oil will b​e motor oil, and filled in the top through a small hole. I will make a plug for that hole on the lathe when it's done to keep chips and dirt out.

Now I cut the piece off at 2" leaving me with a center height of 1" and a 2" swing (swing in American terms.)
Always do machining before you cut the part, so if you make a mistake you only scrap what you messed up on not the whole part like you would if you cut it first. It also makes workholding easier.

BTW, Plans are in 2:1 scale.

Worm outside....(*F)

Now I mill down the saw-cut edge and drill and ream the blind hole for the 3/8" round bed. It will be a very light press fit and held in place with a setscrew. I will keep the bed removable because the setscrews for bearing adjustment are in a hole that runs "through" the bed. I guess I could drill a crosshole through the bed for the hex key, but I probably won't.

Looks like I'm having alu-spaghetti for dinner.

I cut the spindle from a piece of stainless steel printer rod. The bearings are copper pipe, and the bed is some axle or something from something, it's 6" long. That clamping collar was in the junk pile and fit perfectly. The front bearing will be longer than the headstock to rub against this collar to act as thrust bearing surface for cutting force.

Here is everything temporary assembled for picture purposes. I'm having a second wind thinking this may actually work.

Still have to drill for the bearing adjustment set screw holes, tap the bed locking screw, file down the rear of the spindle for a pulley, drill for a oil fill hole, make a stand, and finish the cross slide and toolpost, and make it look pretty of course.

I'm using what I have, plate and bar stock and screws. It was actually DonB that informed me of using plates to make it. He was telling me about a magazine article making a homemade lathe, and I'm sorta using it as an inspiration to build mine. Thanks again, Don!

*******************************UPDATE**********************

Today I drilled, counterbored, and tapped for the bearing adjustment. I also am changing from a round single split bearing to a double split, two piece bearing. The single split bearing was too snug on the spindle and kept turning. The double split two piece bearing didn't spin even at 2800 RPM and lets the spindle turn by hand, which the one piece bearing did not. And makes bearing wear adjustment more sensitive.

Drilling for the 1/4-28 bearing adjustment setscrew.

Since I'm drilling perpendicular to the hole i drilled for the round bed, I have to stop when I break through this wall, re center drill the other side, and continue drilling to prevent the drill from walking.
Here you can see what I mean.

Now since this hole is about 1.6" deep, I need to counterbore for the shank of the tap to get to the bottom of the hole. I didn't feel like grinding the shank of this tap down so I just counterbored it. It also saves time assembling it not having to thread a 28 pitch screw down an inch and a half.

NOTE: I'm counterboring with and endmill for a reason, I'm drilling into the back of the blind hole I drilled for the bed, and if I used drill it would've flexed against the back of the hole. Try drilling halfway into the side of a board if you don't believe me. So I'm using an endmill because it cuts on the side, so any flex there will be self correcting as the tool flexes back to it's normal state.

Tapping for the set screws. I'm not using the machine to tap it because in this case it's impossible (with the counterbore) to start the tap crooked.

Now I assemble it and lap the bearings in on my wood lathe running at 2800 RPM. I still have to finish this tomorrow to wear in the bearings a hair more.

That's it for today.

A

Andre

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Okay, got a bit done today. Angled the top, turned down the back of the spindle (on the mill, using it like a lathe) to fit a pulley, flycut the sides, failed making a 4 jaw chuck, and made a collet blank, and will bore and taper the spindle for a collet next week.

The pulley was from a Hamilton Beach universal (AC, DC, 50-60HZ, 60-120v) motor. I was considering using it for this project, but it was too fast and loud. And even after I rebuilt and cleaned it, it smelled like burning dust. So I am using a Kenmore sewing machine motor, much quieter, slower, and more powerful. Perfect for the project.

It fits. The picture is upside down but you can still see it so I won't bother flipping it.

like a moron I didn't take a picture of milling the 45* angle on the top with a countersink. But here I am flycutting the side. I'm using a round tool with a .25" radius. Nice big swoop, super easy to sharpen and extremely nice finish on aluminum.

Here it is spindle and headstock assembled.

I also started work on making some collets. They are made from the same steel the spindle is made of, a 15* angle on the head and a body diameter of 1.75. I will make a few while i'm at it and bore the spindle with the same angle since I will never have a chance to do it exactly the same again if I move it. That's the way it is with tapers using the scale on my round ram BP.

This lathe will have a maximum capacity of 1/8".

I also did some fitting on the cross slide. I will have to finish it and make the next slide hopefully next week. Then will be a motor mount and box to put it in. If I get that far, cross your fingers!

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Andre,I'm still with you man. You are doing a great job on this. I like the way you are enginering things to be made with the tools you have. You could make a 4 jaw chuck for a lathe this small with small bolts sort of like a spider. Keep up the good work. Mark

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My apologies for missing this thread. I've been pretty busy lately, and I must have breezed right past this a few times. Its looking real good. Thanks for all the pictures and descriptions. This is a great little project.

That was the one I was following during the build. I just need to find a way to cut the t slot. I have no endmills I'm willing to carve up. I did make one from a dowel pin that had a T head on it, but after I ground it I found out I didn't have a collet for it! It's between 1/8" and 3/16"....

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That was the one I was following during the build. I just need to find a way to cut the t slot. I have no endmills I'm willing to carve up. I did make one from a dowel pin that had a T head on it, but after I ground it I found out I didn't have a collet for it! It's between 1/8" and 3/16"....